Morawan Formation | |
---|---|
Stratigraphic range: Chattian | |
Type | Formation |
Unit of | Kawakami Group |
Sub-units | unnamed, Kamirawan, Lower Hard Shale, Middle Hard Shales, Upper tuffaceous silstone |
Underlies | Kiroro Formation |
Overlies | Hombetsuzawa Formation |
Thickness | 500 m (1,600 ft) |
Location | |
Region | Hokkaido |
Country | ![]() |
The Morawan Formation is a Chattian age siliceous marine geological formation of the Oligo- Miocene Japanese Kawakami Group of eastern Hokkaido prefecture. [1] [2] [3] The formation is fossil rich and contains source units where toothed baleen whales ( Aetiocetidae) and Desmostylians have been discovered. [4]
The Morawan Formation is a very siliceous unit containing hard platy shales interbedded with tuffaceous mudstones and sandstones, and some pumice. The unnamed lower member is a hard platy shale alternating with beds of tuffaceous mudstones and sandstones, the Kamirawan member is a tuffaceous sandstone with pumice, the Lower Hard Shale is a very siliceous hard shale with tuffaceous sandstones and mudstones, and the Middle Hard Shales and the Upper tuffaceous siltstone are similar. [5]
Fossil species from the Morawan Formation include:
Morawan Formation | |
---|---|
Stratigraphic range: Chattian | |
Type | Formation |
Unit of | Kawakami Group |
Sub-units | unnamed, Kamirawan, Lower Hard Shale, Middle Hard Shales, Upper tuffaceous silstone |
Underlies | Kiroro Formation |
Overlies | Hombetsuzawa Formation |
Thickness | 500 m (1,600 ft) |
Location | |
Region | Hokkaido |
Country | ![]() |
The Morawan Formation is a Chattian age siliceous marine geological formation of the Oligo- Miocene Japanese Kawakami Group of eastern Hokkaido prefecture. [1] [2] [3] The formation is fossil rich and contains source units where toothed baleen whales ( Aetiocetidae) and Desmostylians have been discovered. [4]
The Morawan Formation is a very siliceous unit containing hard platy shales interbedded with tuffaceous mudstones and sandstones, and some pumice. The unnamed lower member is a hard platy shale alternating with beds of tuffaceous mudstones and sandstones, the Kamirawan member is a tuffaceous sandstone with pumice, the Lower Hard Shale is a very siliceous hard shale with tuffaceous sandstones and mudstones, and the Middle Hard Shales and the Upper tuffaceous siltstone are similar. [5]
Fossil species from the Morawan Formation include: